Plastic support bridge for concrete reinforcing rods



` G. F. ADAMS 3,529,392

PLASTIC SUPPORT-BRIDGE FOR CONCRETE REINFORCNG ROD-S sept. 22, 1910Filed Got. l1, 1968 IN VENTOR.

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United States Patent O PLASTIC SUPPORT BRIDGE FOR CONCRETE REINFORCINGRODS Gerald F. Adams, Redondo Beach, Calif., assignor t ChariotManufacturing Company doing business as Adams Brothers Plastic,Hawthorne, Calif., a corporation of California Filed Oct. 11, 1968, Ser.No. 766,904 Int. Cl. E04c 5/16, 2/38 U.S. Cl. 52-687 4 Claims ABSTRACTOF THE DISCLOSURE A plastic support bridge is provided for supporting amultiplicity of concrete reinforcing rods in an elevated position upfrom a supporting surface as the concrete is being poured, in order thatthe reinforcing rods may be properly positioned within the concrete whenit sets. The bridge to be described is intended to extend transverselyacross the supporting surface, so that when it, and other like bridges,are spaced along the supporting surface they may support the reinforcingrods in, for example, spaced parallel positions, and in a plane parallelto the supporting surface and displaced up from the supporting surface.The bridge to be described is capable of being attached to other similarbridges in a linear relationship, so that as many bridges as arenecessary may be used at each point along the supporting surface toextend across the width of the supporting surface on which the concreteis being poured.

BACKGROUND OF THE INVENTION As is well known, concrete is strong incompression but weak in tension, and it also exhibits a tendency tocrack due to normal shrinkage as it sets, and also due to expansion andcontraction from ambient temperature changes. Therefore, in order toavoid cracking, or when the concrete is to be subjected to tension, ithas been the usual practice for many years to incorporate steelreinforcing rods or bars within the concrete. The resulting concrete andsteel bar combination is commonly known as reinforced concrete.

It is clear that some means must be provided to hold the steelreinforcing bars or rods in position while the concrete is being poured,and until the concrete has set. In the past, this was achieved by wiresor other means. However, the use of wires constitutes an awkward andclumsy way of providing an adequate support for the reinforcing rods.Also, the wires tend to corrode, so that stains often appear on theexposed surface of the resulting concrete structure after it has set.

Copending application 766,806, tiled Oct. 1l, 196'8 discloses and claimsa simple palstic bracket which is used in a snap-on relationship withthe reinforcing rods, so that the rods may be held in position while theconcrete is being poured. The plastic bridge of the present invention isintended to be used for the same general purpose as the individualbrackets of the copending application. The bridges of the presentinvention, for example, nd utility in structures in which a large numberof reinforcing rods are to extend in a generally uniplanar relationshipthroughout the structure.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a perspective view, takenfrom one side, and showing one embodiment of the plastic supportingbridge of the present invention;

FIG. 2 is a plan view of the bridge;

FIG. 3 is a fragmentary representation showing the manner in which thebridge of FIGS. 1 and 2 may be ice attached to other like bridges so asto extend across the entire width of a supporting surface; and

FIG. 4 is a fragmentary representation, partly in section, showing aconcrete block in which reinforcing rods are supported by the bridge ofthe invention.

DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENT As shown, forexample, in FIGS. l and 2, the plastic support bridge of the presentinvention includes a first upright planar member 10, and a plurarilityof interesting triangular-shaped planar -members 12. The planar member10 and the intersecting members 12 may, for example, be formed by highdensity polyethylene plastic, or other suitable material. The bridge maybe injection molded, with the planar members 10, 12 and other componentsal1 being integral with one another.

As also shown in FIG. l, the planar member 10 has arch-shaped openingsformed in it between the support members 12. The support members 12, asshown, may each have an isosceles triangular configuration, and mayextend at right angles to the member 10. The planar member 10 has a bead20 formed at one end, and a socket 22 formed at the other end. Thispermits the bridge to be removably attached to other like bridges, so asto extend across the entire width of a supporting surface. Theattachment is achieved, as shown in FIG. 3, merely by inserting the bead20 of one of the planar members 10 into the socket 22 of another planarmember.

As shown in FIG. 4, for example, the various bridges including theplanar members 10 are placed at spaced positions along a supportingsurface 40. Also, as many planar members are used at each position, asare required to extend completely across the supporting surface. Theadjacent support members are releasably intercoupled in a linearrelationship through their respective beads 20 and sockets 22. p

The various bridges spaced along the supporting surface 40 support aplurality of reinforcing rods, such as the rods 42 in, for example, aspaced and parallel relationship, and in a plane displaced up from thesurface 40. Then, the concrete may be poured, with the reinforcing rods42 being held in the proper positions up from the surface 40. Theconfiguration of the bridge is such that the concrete flows through thearch-shaped openings, and around the planar components, in a manner suchthat a minimum cavity is introduced into the concrete by the variousbridges. This permits the concrete to ow snugly and securely around thereinforcing rods, and its assures that the various support bridges haveno material effect on the homogeneous nature of the resulting structure.

The invention provides, therefore, a simple and inexpensive supportbridge for use in the support of the reinforcing rods While reinforcedconcrete is being poured. The bridges of the invention are extremelyeasy to handle at the construction site, it being merely necessary tostring the bridges across the supporting surface at spaced positionsalong the surface, and then to lay the reinforcing rods across thebridges. After the concrete has been poured, there is no danger whateverof corrosion or staining due to the bridges, and the planar naturethereof assures that the resulting concrete structure will behomogeneous and firmly bonded to the reinforcing rod.

What is claimed is:

1. A plastic support bridge for supporting a plurality of concretereinforcing rods in generally spaced and parallel relationship, saidbridge comprising a first at planar upright member defining a pluralityof arch-shaped openings along the length thereof, and a plurality ofadditional flat planar members intersecting said first planar member atspaced positions along the length thereof between the aforesaidarch-shaped openings and extending transversely to said first planarmember for supporting said first planar member in an upright position,said rst at planar member and said additional planar members beingintegral with one another and formed of a molded plastic material.

2. The plastic support bridge defined in claim 1, in which saidadditional planar members each have a generally triangular shape.

3. The plastic support bridge deined in claim 1, in which saidadditional planar members each have a generally isosceles triangularshape and each extends at right angles to said first 'planar member.

4. The plastic support bridge dened in claim 1, in which said rst planarupright member has a bead formed at one end thereof and socket meansformed at the other end thereof, so as to permit said support bridge tobe attached in a linear relationship with other like support bridges.

References Cited UNITED STATES PATENTS FRANK L. ABBOTT, Primary ExaminerI. L. RIDGILL, JR. Assistant Examiner f U.S. Cl. X.R.

